The present invention relates a process and a device for the positioning of a bobbin which is delivered by a conveying device, wherein the bobbin is tilted from the conveyed position into a position suitable for pick-up by a grasper.
Modern spinning machines are normally provided with conveying devices which receive the bobbins of yarn produced on these machines to store them in intermediary storage and remove them to the packing station. Customarily, yarn bobbins are packed on pallets for shipment in such a manner that the bobbins are placed on the pallet with their axes in upright position in order to protect the layers of yarn. The bobbins which arrive from their winding stations with the bobbin axis in horizontal position must be repositioned in order to be palletized, and must be conveyed from the machine to the pallet with the yarn layers being touched as little as possible.
An automatic handling apparatus with six axles for automatic bobbin removal on a rotor spinning machine (VDI-Nachrichten No. 44; Oct. 30, 1987 page 36 ff.) This machine recognizes the bobbin and its orientation at the end of the conveyor belt of a rotor spinning machine (which ejects the bobbin), grasps it with an electronically controlled grasper, and transfers it under electronic control to a bobbin-conveying carriage. This device is extremely expensive and involves high costs because of the use of a robot controlled via six axles.
A system is also known in which the bobbins are processed by means of palletizing systems and the machine is emptied of bobbins in a fully automatic manner. In order to bring the produced bobbins to the pre-defined location on the pallet, it is necessary to known its exact bobbin position, or the position of the bobbin axis, so as to be able to grasp and transport the bobbin by means of the automatic handling device without damaging it. For this purpose, the bobbins with a horizontal bobbin axis are delivered by the conveyor belt of the spinning machine to the end of the machine with the "Pally" system, and are picked up by the "Pally" palletizing system. When the palletizing system has taken up its position at the end of the conveyor belt, the bobbins are tilted on two parallel conveyor belts. In this case, the tube protruding at the front of the bobbin lies between the belts which support the bobbin on its front side. These parallel belts convey the tilted bobbins to the desired position below a grasping device so that the latter is able to pick up the bobbins in order to place them on a pallet. This arrangement requires much space and is relatively complicated. Electronically controlled search and positioning devices are required so that the pick-up device is able to adjust itself on each spinning machine to the corresponding bobbin size or to the appertaining gap pattern of the intermediate layers.
A device is also known from DE 39 12 683 A1 which consists of a tilting element 25 and a linked positioning conveyor belt 26 as well as of a centering device 35. This tilting element serves to orient the axis of the bobbin vertically by rotating it by 90.degree.. It operates above a horizontal positioning belt conveyor which is designed so that it transfers the bobbins to this positioning belt conveyor 26 after their tilting movement has been executed, to be then transferred by the latter to a centering device which assures the precise positioning of each bobbin so that a grasper 47 may grasp the bobbin and convey it to a loading plane. Three devices, i.e. the tilting device, the positioning, and the centering device, are provided for this arrangement in order to tilt a bobbin and to bring it into a position which is provided for pick-up by a grasper. This arrangement is also relatively complicated and expensive. There furthermore exists the danger that the windings may be damaged at the bobbin's circumference when it is being centered.